Reaction: thioredoxin + ROOH = thioredoxin disulfide + H2O + ROH
For diagram of reaction, click here and for mechanism, click here
Other name(s): thioredoxin peroxidase; bcp (gene name); tpx (gene name); PrxQ
Systematic name: thioredoxin:hydroperoxide oxidoreductase
Comments: Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant proteins. They can be divided into three classes: typical 2-Cys, atypical 2-Cys and 1-Cys peroxiredoxins [4]. The peroxidase reaction comprises two steps centred around a redox-active cysteine called the peroxidatic cysteine. All three peroxiredoxin classes have the first step in common, in which the peroxidatic cysteine attacks the peroxide substrate and is oxidized to S-hydroxycysteine (a sulfenic acid) (see mechanism). The second step of the peroxidase reaction, the regeneration of cysteine from S-hydroxycysteine, distinguishes the three peroxiredoxin classes. For typical 2-Cys Prxs, in the second step, the peroxidatic S-hydroxycysteine from one subunit is attacked by the ‘resolving’ cysteine located in the C-terminus of the second subunit, to form an intersubunit disulfide bond, which is then reduced by one of several cell-specific thiol-containing reductants completing the catalytic cycle. In the atypical 2-Cys Prxs, both the peroxidatic cysteine and its resolving cysteine are in the same polypeptide, so their reaction forms an intrachain disulfide bond. The 1-Cys Prxs conserve only the peroxidatic cysteine, so its regeneration involves direct interaction with a reductant molecule. Thioredoxin-dependent peroxiredoxins are the most common. They have been reported from archaea, bacteria, fungi, plants, and animals.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Kang, S.W., Chae, H.Z., Seo, M.S., Kim, K., Baines, I.C. and Rhee, S.G. Mammalian peroxiredoxin isoforms can reduce hydrogen peroxide generated in response to growth factors and tumor necrosis factor-α. J. Biol. Chem. 273 (1998) 6297-6302. [PMID: 9497357]
2. Kong, W., Shiota, S., Shi, Y., Nakayama, H. and Nakayama, K. A novel peroxiredoxin of the plant Sedum lineare is a homologue of Escherichia coli bacterioferritin co-migratory protein (Bcp). Biochem. J. 351 (2000) 107-114. [PMID: 10998352]
3. Jeong, W., Cha, M.K. and Kim, I.H. Thioredoxin-dependent hydroperoxide peroxidase activity of bacterioferritin comigratory protein (BCP) as a new member of the thiol-specific antioxidant protein (TSA)/alkyl hydroperoxide peroxidase C (AhpC) family. J. Biol. Chem. 275 (2000) 2924-2930. [PMID: 10644761]
4. Wood, Z.A., Schröder, E., Harris, J.R. and Poole, L.B. Structure, mechanism and regulation of peroxiredoxins. Trends Biochem. Sci. 28 (2003) 32-40. [PMID: 12517450]
5. Jeon, S.J. and Ishikawa, K. Characterization of novel hexadecameric thioredoxin peroxidase from Aeropyrum pernix K1. J. Biol. Chem. 278 (2003) 24174-24180. [PMID: 12707274]
6. Perez-Perez, M.E., Mata-Cabana, A., Sanchez-Riego, A.M., Lindahl, M. and Florencio, F.J. A comprehensive analysis of the peroxiredoxin reduction system in the cyanobacterium Synechocystis sp. strain PCC 6803 reveals that all five peroxiredoxins are thioredoxin dependent. J. Bacteriol. 191 (2009) 7477-7489. [PMID: 19820102]